Highway marking composition



. and climatic conditions.

a must be rapid, along with a rapid drying or curing of the markings; Itis important that trafiic not be delayed unduly'while such markings areapplied and cured.

3,046,851 G CGMIGSETEQN Eduard R. de Vries, Huntingdon, Pa, assignor toPrismo Safety Corporation, Huntingdon, Pa., a corporation ofPennsylvania N Drawing. Filed Nov. 24, 1958, Ser. No. 775,690 15 Claims.(Cl. 94-15) surface that can be subjected to trafi'ic within a few eminutes of application to the pavement.

In areas where traffic markings are subjected to heavy abrasive Wear,the usual highway marking paints are not satisfactory because of thenecessity for frequent replacement. Further, the usual highway markingpaints require relatively long drying periods varying from minutes toseveral hours. This interferes with the flow of trailic duringreplacement of the markings for excessively long periods. In the past,these difiiculties have been partially met by the use of preformedmarking devices which may be quickly applied to the pavement surface bymeans of suitable adhesives or other means and which are of sufiicientthickness and durability to withstand long periods of abrasive wear.Such marking may be fairly rapidly applied, however, they do not lendthemselves readily to the production of continuous stripes. Moreover,those which depend upon the use of adhesives are subject to displacementor loss due to the failure of the adhesives under the conditions oftraflic and weathering,

The use of self adhesive plastic materials, which may be applied inthick continuous stripes, has been previously proposed; however,experience has shown that these materials retain a considerable degreeof tackiness during the first few hours after their application, and donot adhere well to the pavement when subjected to trafiic and weatherconditions.

It is therefore an object of the present invention to provide a newtrafiic marking material which may be quickly applied as a continuousstripe and which becomes almost instantly cured to a hard surface andmay be immediately subjected to traflic.

It is a further object of the present invention to provide an improvedtraffic marking material which may be continuously applied to a pavementby spraying and which instantly adheres to the pavement and which onapplication, becomes almost instantly free of surface tackiness.

It is a still further object of the present invention to provide animproved trafiic marking material which may be quickly applied to apavement with glass beads applied thereon and which, almost instantly,cures to a hard material retaining the glass beads in its upper surfaceeven when subjected to traffic conditions.

Markings for pavements of roads, streets, highways,

and the like, have unusual requirements not to be found" in usualcoating compositions. The markings must be durable and wear resistant,for long periods of time, to wear from trafiic and to variousenvironmental changes occasioned by the weather. The markings must beresistant to cracking and chipping, and must adhere satisfac-= torily toa wide variety of pavement material under tranic Application of themarkings 3, 25,851 Patented July 31, 1962 In accordance with the presentinvention, a trafiic marking material which meets the objects of thisinvention can be prepared by admixing a polyester resin containing areactive unsaturated monomer, and an epoxy resin, with pigments,extenders, a catalyst for the polyester resin, an accelerator for thepolyester resin and a curing agent for the epoxy resin. The resultingmarking material has been found to have exceptional adhesion to thepavement, abrasion resistance, low curing time, and a remarkableadhesion to glass beads.

The use of polyester resin compositions as binders in trafiic paints hasbeen previously proposed, however, many shortcomings have been found inthe use of such trafiic paints, Such paints have shown a lack ofabrasion res1stance, a brittleness resulting in cracking under impact,

and a lack of adhesion to pavement surfaces.

Unexpectedly, it has been discovered thatthe addition of the epoxy resinto the polyester resin composition with a simultaneous curing acts toovercome the shortcomings found in either the polyester resincomposition alone or in the epoxy resin alone as the binder.

The main advantage of the polyester resin composition as a binder fortraffic paints is its quick curing time. The main disadvantage of theepoxy resin as a binder for trafiic paints is its slow curing timerequiring from /2 hour to several days for complete curing to permit thepassage of traific. It has now been found that with the combination ofingredients in accordance with the present invention that the curingtime has been reduced to 30 seconds to 10 minutes. It would be expectedby one skilled in the art that the addition of the epoxy resin to thepolyester resin composition would increase the curing time of thepolyester resin composition; however, it has now been found that thesame quick curing time as with the polyester resin composition alone canbe obtained using this mixture of resins.

Thus, utilizing the principles of this invention, a traflic paint isobtained which gives the advantageous properties of the epoxy resin,such as good adhesion and durability, as Well as the advantageousproperties of the polyester resin composition, such as quick curingtime.

To prove this, two sets of samples of trafiic point containing the samepigmentation but with diiferent binders were applied to concrete slabsand submitted to accelerated weathering tests using a weatherometer. Thesamples containing a polyester resin composition alone as the binder inthe traflic paint lasted in the weatherometer test from to 300 hoursuntil failure of the coating. The samples containing the polyester resincomposition admixed with epoxy resin as the binder lasted in theweatherometer test from 500 to 2,000 hours without failure. This testdemonstrates the tremendous increase in durability given to the markerutilizing the compositions of the present invention over previouslysuggested compositions.

The failures noted with the samples containing the polyester resincomposition alone were cracking, chipping and general loss of adhesion.The addition of the epoxy resin results in a composition having a lowershrinkage during curing, thus establishing a firmer bond, coupled withthe better adhesion of epoxy resins. This lower shrinkage substantiallyreduces the strain occurring during and after curing, especially underthe influence of atmospheric humidity, temperature changes, and thelike. It is known that plasticizers, such as dibutylphthalate, act tosoften polyester resins. However, after curing, these monomericplasticizers, which do not take part in the polymerization reaction, arelost by slow volatilization during exposure to atmospheric conditions,thus further increasing slow strain in the fihn leading to cracking. Theepoxy resins, apart from enhancing adhesion in their own right, willevidently also serve as polymeric plasticizers for the cured polyesterresin.

The weatherometer exposure indicated heretofore was in accordance withA.S.T.M procedures except that a freezing cycle of two hours out ofevery twenty-four hours was added, in order to introduce highertemperature differentials and more severe strains.

Traflic paints in accordance with this'invention contain the followingproportions of ingredients:

oxy resin 1-10 (based on the weight or the epoxy present in theformulation) It should be noted that the optimum percentage ofpigmentation is from 40-60% by weight of the composition.

The binder is a combination of a polyester resin composition andan'epoxy resin in the following proportions:

Percent by weight Polyester resin composition (containing theunsaturated monomer) 60-98 Epoxy resin 2-40 It should be understood thatsmall glass spheres having a diameter up to 13 mils can. be incorporatedin these formulae as a premix at a ratio of up to 8 lbs. of spheres pergallon of paint. It is further contemplated that glass spheres of to 40mils in diameter can be distributed onto saturated ethylenic linkage.The polyester reaction products are mixed with a non-volatileunsaturated monomeric cross-linking agent for the polyester resin.Illustrative of the monomeric agents are the unsaturated hydrocarbons,such as styrene, vinyl toluene, vinyl acetate, methyl methacrylate,alpha and para methyl styrene, divinyl benzene, ethyl acrylate,acrylonitrile, diallyl esters, cyclo pentadiene, triallyl cyanurate andmany others. The monomeric agent serves to make the polyester resin morefluid and also to cross-link the resin at the time of curing to producea cross-linked or three dimensional polyester resin, which isthermosetting in character. The monomeric agent is of a nature that itis consumed during the curing of the resin without forming volatilematerials.

The properties of the polyester resin compositions can be modifiedthrough the use of various dibasic acids, difrer'ent glycols, andseveral monomers, each in varying ratio to the others, permittingpreparation of end products with almost any desired properties. Thesepolyester resin compositions are mobile liquids and can be convertedquickly to solids. They are 100% reactive and evolve no gas or liquidduring curing. A specific example of a suitable polyester resincomposition found suitable is the reaction product of- Lbs.

Propylene glycol 974 Phthalic anhydride 888 Maleic anhydride 588Approximately 2200 lbs. of unsaturated polyester reaction product isobtained to which is added 1083 lbs. styrene, or a ratio of 2 partsreaction product to one part styrene. Expressed in mol percent,approximately 5 to or reactive monomer can be added, and the mol.percent of glycol is usually greaterthan the combined mol per.- cents ofthe acids used.

The epoxy resins employed in accordance with the present invention arecommonly referred to as poly 'glycidyl others of polyhydric alcohols andglycidyl ethers of his the surface of the marker before the material hascured. =10: phenols, characterized by the following general formula:

' 0 OH oascmlogo @wssmrsagt (1H in r When the material has cured, theglass beads -are retained in partially embedded state on the surface ofthe marker to yield a high auto-collimating efficiency to the marker.

Rapidly curing liquid polyester resin compositions of a nature suitablefor use in these formulations are known.

In general, suitable polyester resin compositions comprise a polyesterresin and a monomeric polymeri'zablematerial that does not give otfvolatile matter during curingf The suitable polyester'compositions arethose that are commonly' classed as cold cured,polyeste r compositionsthat cure in less than 10 minutes in the presence of a suitable catalystand accelerator without-the necessity of an application of pressure ofan external source of heat.

Polyester resins are a'class of resins, :whicli is well or morepolyhydric alcohols. I Illustrative ofthe dicare boxylic acid componentsare the saturated components phthalic anhydride and adipic and azelai'cacids, and the. unsaturated components, =fumaric acid and maleic acid.

Illustrative of the dihydric alcohols most commonly used are glycolslofethylene, propylene, 1,3- and 2,3 butylene diethylene and dipropylene;'An unsaturatedmonohydric alcohol, such as allyl alcohol, may be used inplace of part of the polyhydric alcohol- '0ne'or more of 'the acidcomdouble bond or ethylenic linkage. It is essential that one of thecomponents of the polyester resins contain an'unwherein n represents theextent of copolyrnerization and varies between 0 and 10 indicatingmolecular weights of 400 to approximately 8000. These products containboth. epoxide and hydroxyl groups capable of further reaction.

a It is the combination or these groups with the curing known to'those'skilled in'the. art. In genera1, polyester resins are unsaturated alkyd'resins formed by the reaction of one or more dicarboxylic acidcomponents and one rial-or resin containing one gram equivalent ofepoxide; Q

.ponents or polyhydric alcohols should'contain a reactive agent thatresults in the cured resin systems. Various amines, such as ethylenediamine, triethylene tetramine,

epoxide equivalency is meant; the average numberpf 1,2- 5

epoxy groups contained in the. average molecule. It is expressed in thetrade as the grains of the polymeric mate- It should be understood thatthe epoxy resins suitable for use this invention are not limited tothose described above. Any resinous material containingreactive epoxygroups whether aliphatic or aromatic, may'b'eused so long as thematerial will cure in the presence of curing agents to a solidcondition. For example,--'a ,dicyclo-diepoxy carboxylate -resin may beused which is sold by -Union Carbide, and Carbon Co. as 'Epoxide' 201. s

The pigment is .added'to the formulation tofimpart reflection to themarker as well as color and opacity, and the extenders impart structuralstrength to the film. To produce a white marker, it is necesary to havea prime pigment, such as rutile titanium dioxide, to furnish thenecessary whiteness and opacity. In place of the rutile titaniumdioxide, anatase titanium dioxide may be substituted. Other pigmentsthat may be used for white and colored markers are as follows: aluminumoxide, iron oxide, silicon carbide, antimony oxides, lead oxide, leadchromates, zinc chromates, cadmium pigments, siennas, timbers, inorganicor organic reds, chrome yellows, chrome oranges, chrome greens, etc. Thepigments can be extended with barium sulphate, calcium sulphate,magnesium silicate, zinc oxides, Zinc sulphide, normal or high strengthlithopones, diatomaceous silica, amorphous and crystalline silica,micaceous materials, barium sulphate, Whiting, wollastonite pumices,calcium carbonate, clay, talc, perlite, asbestos, granular marble, sand,glass beads, and other natural or manufactured granular materials.

Suitable catalysts which are added to the formulation to cure thepolyester resin composition include a large number of oxidizingcatalysts such as lucidol benzoyl peroxide, di-t-butyl peroxide, cumenehydro-peroxide,

methyl ethyl ketone peroxide, benzoyl peroxide, etc. with p which thoseskilled in the art' are familiar. For rapidly curing polyestercompositions, the catalyst at least in part is benzoyl peroxide ormethyl ethyl ketone peroxide.

The accelerators for the polyester composition act to impart glossiness,to minimize stickiness of the material and primarily to decrease thetime necessary for gelation or cure of the resin. Illustrative of themost important accelerators are the cobalt, manganese, vanadium, calciumand iron soaps of organic acids, such as the naphthenates,dimethylaniline, and mixtures of d'unethylaniline with triethylenetetramine or ethylene diamine.

The following specific examples of formulations in accordance with thisinvention are illustrative only and should not be construed as limitingthe scope of the invention:

' Example 1 Parts Polyester resin composition 100 Epoxy resin Vinyltoluene 5 Pigments and extenders 45 Benzoyl peroxide (1:1 in isopropylalcohol) 10 Dimethylaniline 1 Triethylene tetramine l A mixture of thepolyester resin composition, epoxy resin, vinyl toluene, pigments andextenders is made in the usual manner. Immediately prior to use, thebenzoyl peroxide catalyst is added to the mixture and the material isplaced in the supply container of a'line striping machine. The aminesare sprayed from a separate gun in the machine. Thus, the pigmentedbinder is sprayed from the machine and is admixed with the aminesimmediately after leaving the gun. Glass beads can be 'spread on thesurface of the pigmented binder before the curing is complete. The geltime for this formulation was 25 seconds. The line was trafiic dry in 90seconds,

and was nail hard in 2 /2 minutes.

The above composition is a three-part system. The

binder, pigments and extenders, and vinyl toluene are The epoxy resinused was Epon 828 sold by Shell Chemical Corporation.

Example 2 Parts Polyester resin composition 100 Epoxy resin l0Wollastonite (calcium silicate) 32 Titanox (white pigment) l6 Bentone(anti-settling agent) 1 Benzoyl peroxide (1:1 in isopropyl alcohol) l0Dimethyl aniline v l Triethylene tetramine l Toluene 1 v 5 The amineswere dissolved in the toluene and added to a mixture of the remainingingredients. The resulting material had a gel time of 24 seconds and wastrafiic dry in 23 minutes.

Example 3 The same formulation as Example 2 except that 20 parts ofepoxy resin were used.

Example 4 The same formulation as Example 2 except that 30 parts ofepoxy resin were used.

Example 5 The same formulation as Example 2 except that 40 parts ofepoxy resin were used.

Example 6 Parts Polyester resin composition ..L 100 Epoxy resin 20Titanox -13 Wollastonite' 30 Whiting 3 Asbestine i y 1 Dibutyl phthalate5 Benzoyl peroxide (1 :1 in isopropyl alcohol) l0 Dimethyl aniline 1Ethylene diamine 3 Toluol 6 Example 7 Par-ts Polyester resin composition88 Epoxy resin V 10 Vinyl toluene 6 Wollastonite 88 Titanox l5 Bentone lBenzoyl peroxide (1 :1 in isopropyl alcohol) 10 Dimethyl aniline i 1Triethylene tetramine 1 Toluene 3 acts to adjust the viscosity of themixture; however, unlike the solvents in conventional paints, the Vinyltoluene 'copolymerizes with the unsaturated polyester. resin and remainsin the formulation even after curing.

' taining 60% spheres having a diameter up 0 13 The bentone .acts as ananti-settling agent. Aluminum sterate may be substituted for thebentone, if desired, the

anti-settling agent to be used in amounts of 1-5 lbs. per 1 100 galions'of finished material.

Utilizing formulations as described herein, it is possible to apply thelane lines on roads in heavily traveled areas without substantial delayto the passage of trafiic. Liquid spray apparatus for road stripingequipped with two nozzles may be to spray the two materials, withprovision made to have the sprays from the two nozzles meeting near orat the poiutof deposition of the admixture. A movable vehicle, havingmounted thereon two spraying devices, each with a supply tank and spraynozzle, provides a convenient and suitable application utes. The mixtureis applied to the pavement of aroad,

street, highway or the like prior to the curing to the hard, infusiblestate. If reflectorization is desired, glass beads are applied to theupper surface of the marking prior to the curing.

It will be obvious to-th'ose skilled in the art that various changes maybe made without departing from the spirit of the invention and thereforethe invention is not limited to what is described in the specification,but only as indicated in the appended claims.

What is claimed is: r V

l. A highway marking composition consisting essentially of a mixture of4095% by weight of a binder conby weight pigments and extenders therein,said binder comprising a mixture of 60-98% by weight of at least onepolyester resin composition, and 2-40% by weight of an epoxy resin,polymerization catalyst for said polyester resin composition,accelerator for said polyester resin composition and a curing agent forsaid epoxy resin, said polyester resin composition comprising thereaction productof at least one dicarboxylic acid and at leastonepolyhydric alcohol wherein at least-one acid or alcohol componentcontains a reactive double bond,

in admixture with a vinylidene monomer copolymerizab-le therewith, saidepoxy resin comprising at least one resinous material containingreactive epoxy groups curable by said curing agent to a solid state,said mixture having a geltime of less than a minute and cur-ing'toa'trafiic'dry condition within several minutes after addition of saidaccelerator and said curing agent. V

2. A highway marking composition in accordance with" claim 1 whereinsaid polymerization catalyst is benzoyl peroxide, said accelerator isdimet-hyl aniline and said cur- 7 ing agent isselected from the groupconsisting of triethylene tetramineand ethylene diamine. t

3. .A highway marking composition in claim 1 wherein. saidpolymerization catalyst is in accordance with the .4. Am nwaymaikmamount of 110%' by weight of the polyester resin, said accelerator is0.1 -5 by weight ofisaid polyester resin,

and said curing agent is l-% by Weight of the epoxy resin. V 3

5. A highway marking composition in accordance with claim 1 wherein saidmarking composition contains up to 8 lbs. per gallon of the markingcomposition of small glass compositionin accordance with "claim 2wherein said polymerization catalyst is in the 6. A combined highway andsurface marker comprising a road adapted to receive automotive traflic/the upper surface of which is coated with a pigmented composition,

. said composition including a binder containing pigments and extenderstherein, said binder comprising a mixture of 6098% by weight of at leastone polyester resin composition and 2-40% by Weight of an epoxy resin,said mixture of resins being cured by the combination of apolymerization catalyst and accelerator for said polyester resincomposition and a curing agent for said epoxy resin, said polyesterresin composition comprising the reaction product of at least onedicarboxylic acid and at least one polyhydricv-alcohol wherein at leastone acid .or alcohol component contains a reactive double bond, inadmixture with a vinylidene monomer copolymerizabletherewith,e

said epoxy resin comprising at least one resinous material containingreactive epoxy groups curable by said curing agent to a solid state,saidmixture having a gel'time of less than a minute and curing to atraffic dry condition within several minutes after addition of saidaccelerator and said curing. agent. a .7. A combined highway and surfacemarker in accorddance with'claim 6 wherein said'polymerization catalystis benzoyl peroxide, said accelerator is dimethyl aniline and saidcuring agent is selected from the group consisting of triethylenetetramine and ethylene diamine. p 8. A combined highway and surfacemarker in accordance with claim 6 wherein said binder comprises 40-95%by weight of said pigmented composition and said .pi'gments andextenders comprise 560% by weight of said pigmented composition. 7 I

9. A combined highway and surface marker in accord [ance with claim 8wherein said polymerization catalyst is benzoyl peroxide, saidaccelerator is dimethyl aniline and said curing agent is selected fromthe group consisting of triethylene tetra'rnine and ethylene diamine.

10. A combined highway and surface marker in accordance with claim 8wherein said polymerization catalyst is in the amount of l10% by Weightofthe polyester resin, said accelerator is 0.1-5%'by weight of :saidpolyester resin, and said curing agent is 12=0% by Weight of a 1 theepoxy resin.

11. A combined highway and surface marker in accordance with claim9'wherein said polymerization catalyst is in the amount of l-l0% byweight of the polyester resin, said accelerator is 0.l-5% by weight ofsaid polyester resin, and'said curingagent is 1-20% by weight of a j theepoxyre'sin.

12. *A combined highway and surface marker in -ac-, cordance withclaim-dwherein said marking composition contains up to 8 lbsJper gallonof the marking composition of small'glass spheres having a: diameter upto 13 mils.

. 13..A combined highway and surface marker in ac-f cordance with claim6 wherein a plurality of small glass.

sphereshaving a diameter 'of 5 4O mils are partially-embedded in theupper surface of said marker.

polyester resin composition,

an epoxy resin, 5-24 0 parts'by weight pigments and extenders, -1 1Oparts by weight benzoyl peroxide, 0.1-5

parts by weight dimethylaniline, and 0.1-8 parts by weight of a curingagent selected from thegroup, consisting 'of ,triethylenetetramine andethylene diamine, said polyester;

'resin composition comprising least one dicarboxylicacid and at'lea'stone; polyhydrlc a contains a reactive double bond, in admixture acidorialcohol component with a alcohol wherein at least one vinylidenemonomer copolymerizable therewith, epoxy resin comprising atleast" oneresinous material containing reactive epoxy groups curable by saidcuring agent to a solid state, said mixture having a gel-time of lessthan V a minute and curing to a traflic dry condition within several Iing agent.

the reaction product of at minutes after addition of said acceleratorand said'curp 7 15. A method of making a trafiic marker which comprisesapplying a layer of a liquid reflecting pigmented composition to a roadsurface adapted to receive automotive traific, said compositionconsisting substantially entirely of a mixture of 5-6G% by weight ofpigments and extenders, and 40-95% by Weight of a binder, said bindercomprising a mixture of 60-98% by Weight of polyester resin composition,240% of an epoxy resin, 1-10% by weight of said polyester resin of apolymerization catalyst for said polyester resin, 0.1-5 by weight of thepolyester resin of an accelerator for said polyester resin and 120% byweight of the epoxy resin of a cun'ng agent for said epoxy resin, saidpolyester resin composition comprising the reaction product of at leastone dicarboxylic acid and at least one polyhydric alcohol wherein atleast one acid or alcohol component contains a reactive double bond, inadmixture with a vinylidene monomer copolymerizable therewith, saidepoxy resin comprising at least one resinous material containingreactive epoxy groups curable by said curing agent to a solid state,adding said accelerator and said curing agent to the remainder of thecomposition immediately prior to the composition reaching said roadsurface whereby said polyester resin and said epoxy resin are catalyzedand cured on said road surface to form a thermoset solid incorporatingsaid pigment and extenders which is adherent to said road surface andresistant to the abrasion of traffic.

References Cited in the file of this patent UNITED STATES PATENTS2,574,971 Heltzer Nov. 13, 1951 2,824,502 Rockwell et a1. Feb. 25, 19582,865,266 Wynn Dec. 23, 1958 2,897,733 Shuger Aug. 4, 1959 FOREIGNPATENTS 735,531 Great Britain Aug. 24', 1955

1. A HIGHWAY MARKING COMPOSITION CONSISTING ESSENTIALLY OF A MIXTURE OF40-95% BY WEIGHT OF A BINDER CONTAINING 5-60% BY WEIGHT PIGMENTS ANDEXTENDERS THEREIN, SAID BINDER COMPRISING A MIXTURE OF 60-98% BY WEIGHTOF AT LEAST ONE POLYESTER RESIN COMPOSITION, AND 2-40% BY WEIGHT OF ANEPOXY RESIN, POLYMERIZATION CATALYST FOR SAID POLYESTER RESINCOMPOSITION, ACCELERATOR FOR SAID POLYESTER RESIN COMPOSITION AND ACURING AGENT FOR SAID EPOXY RESIN, AND POLYESTER RESIN COMPOSITIONCOMPRISING THE REACTION PRODUCT OF AT LEAST ONE DICARBOXYLIC ACID AND ATLEAST ONE POLYHYDRIC ALCOHOL WHEREIN AT LEAST ONE ACID OR ALCOHOLCOMPONENT CONTAINS A REACTIVE DOUBLE BOND, IN ADMIXTURE WITH AVINYLIDENE MONOMER COPOLYMERZIBLE THEREWITH, SAID EPOXY RESIN COMPRISINGAT LEAST ONE RESINOUS MATERIAL CONTAINING REAVTIVE EPOXY GROUPS CURABLEBY SAID CURING AGENT TO A SOLID STATE , SAID MIXTURE HAVING A GEL TIMEOF LESS THAN A MINUTE AND CURING TO A TRAFFIC DRY CONDITION WITHINSEVERAL MINUTES AFTER ADDITION OF SAID ACCELERATOR AND SAID CURINGAGENT.